§ 136. Contracts in pursuance of appropriations. A contract or contracts made in pursuance of an appropriation by the state for a specific object shall be for the completion of the work contemplated by the appropriation, and in the aggregate shall not exceed the amount of such appropriation. A contract for a part of such work shall not be binding upon the state until contracts are also made covering the entire work contemplated by such appropriation, except that, (a) upon certification by the agency having jurisdiction to the state comptroller that sufficient appropriations remain for completion of the entire work contemplated, preliminary work such as site preparation and infrastructure work may be commenced for a project where the timeliness thereof is of the essence and the director of the budget certifies to such need and to the availability of appropriations, and except (b) where it is expressly provided by such appropriation that a part of the work may be done by day's labor. Except as provided in § 38 of the highway law, every such contract shall be accompanied by a bond for the completion of the work, specified in the contract, within the amount stipulated therein, which bond shall be filed in the office of the state comptroller.